NEENAH - The owners of Fox Valley Energy Center now have until March 4 to demolish the building.

City Council members unanimously approved an extension of the project — from Dec. 31 to March 4 — at a meeting Wednesday night. The company could still receive $150,000 from the city if all project requirements are met by March 4.

Two-thirds of the $150,000 will be paid by an undisclosed donor. The other third will come from $35,000 in sales of crushed concrete from the demolition, and $15,000 from tax dollars.

The structure, at 231 Millview Drive, is on public land at Arrowhead Park. The plant was built on leased land more than 20 years ago to recycle paper sludge from nearby mills. But the supply of paper sludge dried up as more mills closed, so the center shut down in June 2013.

More than 4 million tons of paper sludge was recycled during its 15 years of operation.

The city has a strong interest in seeing the structure gone, said Mike Easker, city finance director, to both eliminate blight and encourage better waterfront development near downtown Neenah.

Demolition of the building began in January, but a dispute between the company and its demolition contractor brought the project to a halt later that spring.

The initial demolition deal between the city and the building owners was approved in November 2014.